Justin read 1/8 of a book the first day, 1/3 the second day, and ¼ the third day. on the fourth day he finished the book. what part of the book did justin read on the fourth day?

First, make the fraction a common denominator.
1/8 becomes 3/24
1/3 becomes 8/24
1/4 becomes 6/24
Reading a whole book is equal to 1 so you can subtract what you already read to see what Justin read on the fourth day.
1 can also be written as 24/24.
24/24-3/24-8/24-6/24=7/24
So, Justin read 7/24 of the book on the fourth day.

Hope this helped! :)

Just a second zzz